Teach iic(4) the 'repeated start' I2C condition. This will be used by the

upcoming i2c(8) diag utility.

Reviewed by:	bms, stas
Obtained from:	Semihalf

share/man/man4/iic.4

@@ -45,13 +45,19 @@ In order to control I2C devices, use
 .Pa /dev/iic?
 with the
 following ioctls:
-.Bl -tag -width ".Dv I2CRSTCARD"
+.Bl -tag -width ".Dv I2CRPTSTART"
 .It Dv I2CSTART
 .Pq Vt "struct iiccmd"
 Sends the start condition to the slave specified by the
 .Va slave
 element to the bus.
 All other elements are ignored.
+.It Dv I2CRPTSTART
+.Pq Vt "struct iiccmd"
+Sends the repeated start condition to the slave specified by the
+.Va slave
+element to the bus.
+All other elements are ignored.
 .It Dv I2CSTOP
 No argument is passed.
 Sends the stop condition to the bus.

sys/dev/iicbus/iic.c

@@ -368,6 +368,11 @@ iicioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *t
 		}
 		free(usrbufs, M_TEMP);
 		break;
+
+	case I2CRPTSTART:
+		error = iicbus_repeated_start(parent, s->slave, 0);
+		break;
+
 	default:
 		error = ENOTTY;
 	}

sys/dev/iicbus/iic.h

@@ -60,5 +60,6 @@ struct iic_rdwr_data {
 #define I2CWRITE	_IOW('i', 4, struct iiccmd)	/* send data */
 #define I2CREAD		_IOW('i', 5, struct iiccmd)	/* receive data */
 #define I2CRDWR		_IOW('i', 6, struct iic_rdwr_data)	/* General read/write interface */
+#define I2CRPTSTART	_IOW('i', 7, struct iiccmd)	/* repeated start */
 
 #endif